Address book and personal organizer are two most common features used in personal communication devices such as mobile phones. Address book provides users means to store contact information of businesses and individuals. Usually address book provides users means to store contact information such as name, address, phone, fax, email, web site etc. In addition most modern personal communication devices enable speed dial of phone numbers contained in entry of address book. Personal organizer provides users means to enter planned tasks according to anticipated time of execution of corresponding tasks. Usually users are able to enter anticipated tasks into the personal organizer according to anticipated time of task i.e. date, day of the week, year, hour and minute etc. Most personal organizer systems have alarm feature to remind users of a task at a time prior to entered time of task as selected by user. However, another important feature applicable to any task i.e. location of anticipated task is not incorporated in any personal organizer system currently in use. Although personal organizer systems currently in use are able to remind users of tasks as a function of time, this sometimes is not useful as user is not present at the location of task at the time of reminder and hence is unable to execute said task. Moreover many tasks are location critical as opposed to time critical. For example user may want to be reminded to purchase milk when user is in a grocery store, irrespective of the time. Hence there remains a need for personal organizer system that enables user to be reminded of task as a function of location of user.